Wireless communication systems are inherently subject to radio interference. The interference may come from a number of sources, including, for example, (i) radio systems operating on nearby frequencies that ‘leak’ energy into the operating channel; (ii) radio systems operating on the same frequency with an unknown access pattern or a modulation that cannot be understood, such as a cordless telephone; (iii) devices that emit radio frequency (RF) energy as a side effect, such as personal computers and certain types of lighting; (iv) devices that emit radio frequency (RF) by design, but are not capable of negotiating to share the channel or follow a channel access protocol, such as microwave ovens and radar systems; and (v) radio systems that are capable of negotiating to share a radio channel but consume too large a portion of the available channel capacity.
Wireless communication devices are often configured to operate on a fixed radio channel. In other implementations, a user's interaction may be required to notify the device that there is too much interference and that a jump to a different channel is desired. Often, this causes a perceivable interruption of the communication service. For example, in the presence of too much interference in an audio communication system, a user may detect a noise, such as a click, or the sudden absence of sound. Similarly, in a video communication system, a user may detect jerky movements or otherwise distorted images. For a data communication system, however, the interruption in communication service is generally less noticeable because the data transfer is typically less time-critical.
A need therefore exists for methods and apparatus that can automatically detect when an operating channel needs to be changed in a wireless communication system. A further need exists for methods and apparatus for automatically determining when to change the operating channel and automatically selecting a new operating channel. Yet another need exists for methods and apparatus that can automatically change an operating channel, while minimizing the time that the communication service is disrupted so that the channel jump has minimal perceivable effects to the user.